Is method for switching TPU counter clock from φ/256 to φ/16 valid?

Question:

Is the following method for switching the TPU counter clock from φ/256 to φ/16 valid: set the TGRA of the 16-bit TPU to toggle output, generate a TGRA compare match interrupt, and switch the current TPU counter clock during that interrupt?

Answer:

Yes. However, the counter clock can only be modified by methods which reactivate count after the counter clock has been changed after a count stop.